Fire extinguisher



July 24, 1962 E. J. CIARLO 3,045,761

FIRE EXTINGUISHER Filed Sept. 22, 1960 INVENTOR fuqene d. Ciar/o ATTORNEYS United States Patent Office 3,415,761 Patented July 24, 1962 3,945,761 FHiE EXTINGUISEER Eugene J. Ciarlo, 308 Front Ave, West Haven, Conn. Filed Sept. 22, 1960, Ser. No. 57,817 Claims. (Cl. 169-31) This invention relates to foam fire extinguishers and relates more particularly to fire extinguishers of the stored-pressure type. These extinguishers are pressurized when they are filled and are unlike the type of foam extinguisher which is pressurized by the mixing of chemicals, as by inverting the fire extinguisher, only immediately prior to use of the extinguisher to fight a fire.

Heretofore, stored-pressure extinguishers of the foam type have employed a gas, such as Freon, as a pressurizing medium or propellant. The use of Freon complicates the recharging of a foam extinguisher and also adds to the cost of recharging the extinguisher.

One object of the invention is to provide an improved foam extinguisher of the stored pressure type.

Another object is to obviate the use of a gas, such as Freon, as a pressurizing medium or propellant and make use of compressed air in its place.

Still another object is to provide an extinguisher such as characterized above, in which there is improved mixing of the pressure medium and the foaming solution to produce a superior foam.

In the accompanying drawing:

FIG. 1 is a side elevational view of an extinguisher embodying the invention, the extinguisher being partially broken away to better illustrate certain parts of the structure;

FIG. 2 is a top plan view of the extinguisher;

FIG. 3 is an enlarged sectional view taken on line 33 of FIG. 2;

FIG. 4 is a sectional view taken on line 4-4 of FIG. 3; and

FIG. 5 is a sectional view taken on line 5--5 of FIG. 3.

In the drawing the usual steel tank of the extinguisher is indicated at 10, and this tank is provided with a neck portion 11 through which the tank is charged and dis-- charged. A manually operable valve mechanism, indicated generally at 12, is supported on the neck portion of the tank to control the discharge of the contents of the tank. This mechanism includes a valve housing or block 1 3 provided with a lower neck portion 14 which has a reduced part externally threaded to receive an internally threaded flange 15. This flange presents an annular shoulder which is abutted by a similar shoulder of a flange 16. The flange 16 is internally threaded for cooperation with external threads formed on the neck portion 11 of the tank and the arrangement is such that the flanges 15 and 16 mount the valve mechanism 12 on the tank very securely but releasably. As shown in FIG. 3, a gasket 17 of annular form is interposed between the neck portion 11 of the tank and the flange 15 toprovide a liquid-andpressure seal.

An eductor tube, indicated generally at 18, extends downwardly into the tank from the valve mechanism 12 and approaches the bottom of the tank. As shown in FIG. 3, the tube 18 at the upper end thereof is externally threaded and is secured in an upwardly extending duct 19 formed in the valve housing 13. The duct 19 at the upper end thereof exits into a pressure-reducing and mixing chamber 20 formed in the housing 13. The chamber 20 communicates with a chamber 21 (formed in the valve housing) through an orifice 22 controlled by a manually operated valve, indicated generally at 23. The chamber 21 communicates with the discharge orifice 24 of the valve mechanism. The size of this orifice is somewhat exaggerated as it is shown in FIG. 3. In actual practice the size of the orifice may be in the neighborhood of one thirty-second of an inch. A retaining sleeve 25 is threaded on the valve housing 13 in embracing relationship to the orifice 24 and has a flange which abuts a flange of an inner tubular part 26 over which the flexible hose 27 of the extinguisher has a tight fit. The last-named abutting flanges cooperate in the manner shown in FIG. 3 and prevent the hose 27 from being blown off the extinguisher when the valve 23 is opened to discharge the contents or a part of the contents of the tank. The hose is provided with the usual discharge nozzle 28 as shown in FIG. 1.

As best shown in FIGS. 3 and 4, the valve housing 13 is provided with a pressure duct 29 opening into the mixing chamber 29 through a port 30 controlled by a needle valve 31. The inlet end of the pressure duct 29 communicates with the neck of the tank well above the fluid level therein and is arranged externally of the siphon tube 18, as shown in FIG. 4. The functions of the duct 29 will appear hereinafter. The tank is pressurized through a valve 32 (FIG. 2) extending through the 'wall of the tank in the upper region thereof. The valve 32 may be of construction similar to Valves commonly found in automobile tires, and to pressurize the tank an air hose, such as commonly found in automobile garages connected to a source of compressed air, may be placed over the valve 32 and the latter opened. A conventional pressure gauge 33 is provided to indicate the pressure in the tank which, when the tank is charged, should preferably be in the approximate range of to lbs. per square inch. As shown in FIG. 5, the gauge is threaded, as at 34-, into a port 35 in the valve casing 13. The port 35 is connected through a cross duct 36 with a duct 37 vertically arranged in the valve housing 13 and having its mouth or inlet arranged near the neck of the tank above the liquid level.

The siphon tube 18 which extends down into the tank has intermediate of its ends a pressure-relieving and flowretarding chamber 38. The lower end of the tube 18 is constituted by a tubular element 39 having closed ends and extending some distance into the expansion chamber 38. The side wall structure of the tubular element 39 is provided with a series of small perforations 40, some of the perforations 40 being formed in the portion of the element 39 within the expansion chamber 38' and others being formed in the element 33 without the chamber 38, as shown in FIG. 1. These small perforations create a turbulence in the solution to initiate the foaming action as the solution enters the tubular element 39 under the influence of the pressure in the tank. The foam expansion chamber 38 in the tube 18, which is in communication with the tubular element 39, retards the speed of the flow of the solution in the tube 18. It will be understood from the foregoing that the foaming solution is restricted as it passes from the expansion chamber 38 to the valve mechanism 12.

The aforementioned valve 23, which controls the discharge of the fire extinguisher, has intermediate of its ends an enlarged frusto conical portion 39 to cooperate with the valve seat 22. The valve 23 has above the portion 39 a stem portion 40 terminating upwardly in a stem portion 41 of reduced diameter. The stem portion 40 is vertically slidable in a pressureand solution-tight bushing 42 threaded into the valve casing 13 (FIG. 3) and topped by a cap 43 threaded thereon. The cap 43 forms an abutment for the upper end of the stem portion 40 and slidably receives only the reduced stem portion 41. Below the valve portion 39 the valve 23 is provided with a stem portion 44 which is loosely embraced by a compression spring 2.3 reacting against the valve portion 39 and a plug 46 threaded into and sealing an opening in the valve housing below the valve 23, the opening sealed by the plug 46 being indicated at 47 (FIG. 3). As indicated in the a last-mentioned view, the valve 23 may be assembled in the valve casing 13 through the opening 47. The compression spring 23 biases the valve 23 toward the closed position thereof, and, as shown in FIG. 3, the plug 46 may be provided with an upwardly extending socket 46 in which the stem portion 44 may bottom to limit Opening movement of the valve.

The upper end of the valve stem portion 41 may press against the under side of a valve-actuating lever 48 intermediate the ends of the latter. One end of the lever is pivoted, as at 49, between upstanding ears St) on the valve casing, the arrangement being such that the lever may be swung downwardly to open the valve 23 through downward movement of the valve stem portion 41 engaged by the lever. The other end of the lever may be grasped for this purpose. This end of the lever extends through and beyond an invertedV-shaped member 52 upstanding on the valve casing 13 and preferably formed integrally therewith, as shown in FIG. 3. As the valve-actuating lever 48 extends through the member 52 in the manner shown in the last-mentioned view, upward swinging movement of the lever 48 is limited by the lever 52.

A releasable locking device is provided to lock the lever 48 in its inoperative position when the extinguisher is stored or being transported, as in a vehicle. This device includes a pull pin 51 extensible through a transverse bore in the lever 48 and into the arms of the inverted U-shaped member 52. The pin 51 may be provided with a ring 56 (FIG. 1) permanently secured to one end thereof. The ring 56 may be grasped and pulled for quick removal of the pin. A lifting and supporting handle 53 is provided for the fire extinguisher, the handle in the illustrated form being generally of inverted channel shape and being piv oted, as at 54, for vertical swinging movement. This swinging movement of the handle 53 in an upward direction is limited by engagement of flanges 53 of the lever with the top of the valve casing 13 when the handle is in the position shown in broken lines in FIG. 1. As best shown in FIG. 2, the tank of the extinguisher on the upper external region thereof is provided with a strap 57 by which the fire extinguisher may be supported from a wall through a bracket, not shown.

The extinguisher may be charged with water and a foaming agent through the neck of the tank after removal of the valve mechanism. The valve mechanism may be very easily removed by completely unthreading the holddown flange 16 from the neck of the tank and then lifting the valve mechanism off the neck. In the presently preferred form, the tank is of a size to accept two gallons of water to which is added the usual amount of a conventional foaming agent. This fills the tank to a point just below the expansion chamber 38 of the siphon tube. It is important that the level of the solution remain below the expansion chamber 38. After the tank is charged with a solution of water and a foaming agent in the manner described above the valve mechanism may be replaced on the top of the tank and firmly clamped down by the threaded flange 16. The tank may then be pressurized by applying an air hose to the valve 32' in the manner described above, and as previously indicated it is preferred that the tank have a charge pressure of approximately 80 to 120 lbs. per square inch. It will be manifest from the foregoing that the gauge 33 indicates the pressure in the tank. The gauge may be checked after the extinguisher has been in storage for a considerable length of time to enable the user to ascertain whether there has been any drop in pressure in the tank.

When it is desired to use the extinguisher, the locking pin 51 is first removed in the manner indicated above. The extinguisher may be supported from the handle 53. The valve 23, controlling the discharge of foam from the extinguisher is opened by swinging the valve actuating lever 48 downwardly in the manner previously described. In this connection, the lever 48 and the pivoted handle 43 4 may be squeezed together to support the extinguisher and effect a discharge of foam therefrom.

When the valve 23 of the extinguisher is opened there is a reduction of pressure in the mixing chamber 20 and the chamber 40 then in communication therewith and in communication with the discharge orifice 24 of the valve mechanism. This reduction of pressure causes the pressurized solution in the tank to be forced through the small apertures into the tubular element 39 in the lower portion thereof, thus creating a turbulence. The pressurized solution is then forced out of the upper small apertures in the tubular element 39 into the expansion chamber 38 when the foaming action of the solution commences if it has not commenced, at least to some extent, when it entered the tubular element 39. Foam is generated in the chamber 38 and collected therein and then forced, through the pressure in the tank, up the tube 18 to the mixing chamber 29. In the chamber 20, the foam, which was previously restricted in the upper part of the tube, is permitted to re-expand and in this chamber is further aerated, a very important advantage of the extinguisher.

The air from the tank above the solution passes into the chamber 20 under substantial pressure through the duct 29 having its mouth portion near the neck of the tank but externally of the tube. Air under pressure in the duct passes the port 30 entering the mixing chamber 20 and in this area of the port is closely controlled by the needle valve 31 which may be adjusted to restrict or enlarge the port 30. As shown in FIG. 4, the needle valve 31 is threaded downwardly into the valve casing 13 through the top thereof and is accessible above the valve casing for screw adjustments. The air entering the chamber 20 upon pressure mixes thoroughly with the foam in the chamber and greatly increases the foam generation. When the valve 23 is open, foam further generated in the mixing chamber 20 may pass to the discharge orifice 24 to exit therefrom into the hose 27 from which it is discharged through the nozzle 28. The discharge of foam from the extinguisher may be terminated quickly by merely releasing the valve-actuating lever 48.

It will be manifest from the foregoing disclosure that there is provided an improved foam extinguisher of the stored-pressure type and it will also be apparent that the extinguisher has the advantage of employing a gas in the form of air as a pressurizing medium rather than a gas, such as Freon. Of course, Freon may be employed as a pressurizing medium, if desired. Furthermore, the extinguisher is provided with improved means for mixing of the pressure medium and the foaming solution to increase the foaming action in the extinguisher. The extinguisher is constructed of relatively few parts. It has no moving parts within the tank and the tank consists of a single compartment which is employed in accordance with the disclosure to hold both the foaming solution (i.e. water and a foaming agent) and the pressurizing medium. Still another advantage of the extinguisher resides in the fact that it may be charged by a very simple operation and may be charged with substances which may be readily available. If desired, the foaming agent may be omitted from the water in the tank and th extinguisher used, not as a foam generator, but as a storedpressure dispenser of water only.

While only one form of the extinguisher has been shown in the drawing and described above, it Will be apparent to those versed in the art that the extinguisher may take other forms and is susceptible of various changes in details without departing from the principles of the invention and the scope of the appended claims.

What I claim is:

1. In a foam fire extinguisher of the stored-pressure type, a tank having means defining a discharge opening and forming a container for holding a foam-generating solution, consisting of water and a foaming agent, and a pressurizing gas above the level of the solution, an eductor tube extending downwardly in the tank below the solution level and approaching the bottom of the tank, and a valve head assembly supported from the tank over said means and having a first passage, controlled by a manually operable valve, communicating with the tube and extending to a foam-discharging orifice, said first passage having an expansion and mixing chamber within said assembly adjacent and behind said valve, the valve head assembly having a second passage communicating with the pressurizing gas space and said chamber, whereby the gas and the solution are intimately mixed to generate foam in the valve mechanism just prior to passing said valve.

2. In a foam fire extinguisher of the stored-pressure type, a tank having means defining a discharge opening and forming a container for holding a foam-generating solution, consisting of water and a foaming agent, and a pressurizing gas above the level of the solution, an eductor tube extending downwardly in the tank below the solution level and approaching the bottom of the tank, and a valve head assembly supported from the tank over said means and having a first passage, controlled by a manually operable valve, communicating with the tube and extending to a foam-discharging orifice adjacent but beyond the valve, said first passage having a mixing and expansion chamber directly behind the valve, the valve head assembly having a second passage communicating with the pressurizing gas space and said chamber, whereby the gas and the solution are intimately mixed to generate foam in the valve mechanism just prior to passing said valve, and said valve mechanism including a second valve, which is adjustable and which controls said second passage.

3. In a foam fire extinguisher of the stored-pressure type, a tank having means defining a discharge opening and forming a container for holding a foam-generating solution, consisting of water and a foaming agent, and a pressurizing gas above the level of the solution, an eductor tube extending downwardly in the tank below the solution level and approaching the bottom of the tank, said tube having an expansion chamber above the solution level and having a tub part extending downwardly into the solution and provided with a multiplicity of openg in e a s r ct re t e eo o create a t b en e in the latter as it is drawn into the tube, and a valve head assembly supported from the tank over said means and having a first passage, controlled by a manually operable valve, communicating with the tube and extending to a foam-discharging orifice, the valve head assembly having a second passage communicating with the pressurizing gas space and an expansion and mixing chamber formed in said first passage directly behind said valve, whereby the gas and the solution are intimately mixed to generate foam in the valve mechanism just prior to passing said valve.

4. In a foam fire extinguisher of the stored-pressure type, a tank having means defining a discharge opening and forming a container for holding a foam-generating solution, consisting of water and a foaming agent, and a pressurizing gas above the level of the solution, an eductor tube extending downwardly in the tank below the solution level and approaching the bottom of the tank, said tube having an expansion chamber above the solution level and having a tube part extending downwardly into the solution and provided with a multiplicity of openings in the wall structure thereof to create a turbulence in the latter as it is drawn into the tube, and a valve head assembly supported from the tank over said means and having a first passage, controlled by a manually operable valve, communicating with the tube and extending to a foam-discharging orifice, the valve head assembly having a second passage provided with an inlet externally of the tube and communicating directly between the pressurizing gas space and an expansion and mixing chamber formed in the first passage behind said valve, whereby the gas and the solution are intimately mixed to generate foam in the valve mechanism just prior to passing said valve.

5. A foam fire extinguisher as defined in claim 4 wherein an adjustable valve is provided for controlling the discharge of said second passage into last-named chamber.

References Cited in the file of this patent UNITED STATES PATENTS 2,381,475 Urquhart Aug. 7, 1945 2,745,700 Phalen May 15, 1956 2,878,965 Hirt et a1. Mar. 24, 1959 2,908,334 Duggan et a1. Oct. 13, 1959 

